关于SqlConnection的疑问
我通过
Dim thisConnection As New SqlConnection
thisConnection.Open()
Dim sql_check As String
Dim cmd As New SqlCommand
cmd.Connection = thisConnection
cmd.CommandText = sql_check
Dim dataReader As SqlDataReader = cmd.ExecuteReader()
这样的方式来读取数据.
现在遇到个问题,我需要多次调用thisConnection,但是我发现我必须多次创建thisConnection 才能运行程序.
假如我用cmd_1.Connection = thisConnection 就会错误.必须创建想同的thisConnection_1,运行cmd_1.Connection = thisConnection_1 才会正常通过.有什么方法会可以多次调用一个SqlConnection
[解决办法]
你每次打开数据库连接后必须先关了才可以下次打开
thisConnection .Close()
或者在不关闭连接的时候
dataReader.Close()
cmd.CommandText = sql_check
dataReader = cmd.ExecuteReader()
